1. Field of the Invention
The present invention relates, in general, to fresh, unripened cheese analog and a method for making a fresh, unripened cheese analog by incorporating isolated soy protein. The invention also relates to hard, ripened cheeses or cheese analogs and methods for making hard, ripened cheeses or cheese analogs by incorporating isolated soy protein.
2. Background Information
While the art of cheesemaking has been practiced for centuries, the cheesemaker is always looking for ways to improve the finished cheese yield obtained from the starting quantity of milk. This becomes very important in areas of the world where the milk supply is limited. Attempts have been made over the years to incorporate soy protein as an economic replacement for milk proteins. Problems can be encountered due to differences between milk and soy proteins in molecular and functional properties which can affect the quality of the finished cheese.
Therefore, a method is provided which incorporates isolated soy protein into a coagulated milk matrix.
The invention provides a method for making a fresh, unripened cheese analog comprising, (a) mixing isolated soy protein and milk; (b) adding a coagulating agent, and/or bacterial cultures to said mixture from (a); (c) cutting the product resulting from (b); (d) agitating the product resulting from (c) for about 40 to about 60 minutes at a temperature selected from the range of about 30xc2x0 C. to about 50xc2x0 C.; (e) separating about 50 to about 80% of whey from product resulting from (d); and (f) placing product resulting from (d) in molds and placing molds at a temperature of at least about 28xc2x0 C. for about 2 to about 8 hours.
The invention also relates to a method for making a hard, ripened cheese or cheese analog comprising (a) mixing isolated soy protein and milk; (b) adding a coagulating agent, and/or bacterial cultures to said mixture from (a); (c) cutting product resulting from (b); (d) agitating the product resulting from (c) for about 40 to about 60 minutes at a temperature of from about 30xc2x0 C. to about 70xc2x0 C.; (e) separating about 50 to about 80% of whey from product resulting from (d); (f) processing the product resulting from (e) to produce the desired type of cheese or cheese analog; and (g) placing product resulting from (f) in molds and placing the molds at a temperature appropriate for the desired type of cheese or cheese analog, for a length of time necessary to begin the ripening process.
The invention provides a method for making a fresh, unripened cheese and cheese analog comprising, (a) mixing isolated soy protein and milk; (b) adding a coagulating agent, and/or bacterial cultures to said mixture from (a); (c) cutting the product resulting from (b); (d) agitating the product resulting from (c) for about 40 to about 60 minutes at a temperature selected from the range of about 30xc2x0 C. to about 50xc2x0 C.; (e) separating about 50 to about 80% of whey from product resulting from (d); and (f) placing product resulting from (d) in molds and placing molds at a temperature of at least about 28xc2x0 C. for about 2 to about 8 hours.
The invention also relates to a method for making a hard, ripened cheese or cheese analog comprising (a) mixing isolated soy protein and milk; (b) adding a coagulating agent, and/or bacterial cultures to said mixture from (a); (c) cutting product resulting from (b); (d) agitating the product resulting from (c) for about 40 to about 60 minutes at a temperature of from about 30xc2x0 C. to about 70xc2x0 C.; (e) separating about 50 to about 80% of whey from product resulting from (d); (f) processing the product resulting from (e) to produce the desired type of cheese or cheese analog; and (g) placing product resulting from (f) in molds and placing the molds at a temperature appropriate for the desired type of cheese or cheese analog, for a length of time necessary to begin the ripening process.
The milk used in the present invention may be present in amounts of from about 95% to about 99.99%, and preferably from about 98% to about 99.99%. The milk may comprise of from about 0% to about 10% fat and preferably from about 0.5% to about 5% fat. It may be desirable to use milk with a low fat content and optionally add fat from other sources. As such, the fat contained in the milk may originate from at least one of the compounds of the group comprising milkfat or vegetable oil.
The invention provides the above and below described methods wherein said soy protein is present in amounts of from about 10% to 100% by weight, and preferably from about 15% to about 50%. By xe2x80x9cpercentxe2x80x9d it is meant weight percent based on the calculated amount of casein solids in the milk. The isolated soy protein used in the present invention may be prepared by pH adjusting soy curd prior to spray drying or by blending different isolated soy proteins to obtain the desired pH. The pH of the isolated soy protein(s) may be of from about 3 to about 7, and preferably of from about 4.5 to about 6.0.
In one embodiment, the present invention provides a method of making a fresh, unripened cheese analog by adding at least one compound to a mixture of isolated soy protein and milk, wherein said compound is selected from the group comprising transglutaminase, starch, a whitening agent, hydrocolloid gum, calcium chloride, and a coagulating enzyme.
In another embodiment, the present invention provides a method of making a hard, ripened cheese or cheese analog by adding at least one compound to a mixture of isolated soy protein and milk, wherein said compound is selected from the group comprising transglutaminase, starch, a whitening agent, hydrocolloid gum, calcium chloride, and a coagulating enzyme.
Transglutaminase is an enzyme which crosslinks proteins and which aids in crosslinking the isolated soy protein and milk proteins. The transglutaminase catalyzed crosslinks serve to compatibilize the soy and milk proteins. These crosslinks help in improving the functionality of the different proteins and therefore improving the texture of the finished product. Transglutaminase is preferably present in amounts from about 0% to about 1.0%, and preferably from about 0% to about 0.2%.
As a binder or filler in the cheese, generally any starch which is at least partially soluble in water at the described temperatures can be employed in the cheese or cheese analog making method of the present invention. Corn and potato starches are types of binder that may be used. The preferred starch should be pregelatinized by mixing with water and heating to its gelatinization temperature prior to addition to the milk. The gelatinized starch may optionally be added in amounts of from about 0% to about 20%, and preferably from about 0% to about 10%.
Often it is desirable to produce a cheese analog with a white appearance. As such, the present invention provides for the optional addition of a whitening agent in amounts of from about 0% to about 0.5%, preferably from about 0% to about 0.1%. The whitening agent must be chemically inert and harmless to the animal or human who ingests the agent, but, of course also must make the appearance of the cheese white. The invention provides the herein described methods wherein said whitening agent may be selected from the group comprising titanium dioxide, benzoyl peroxide, or green and blue food colorings.
A hydrocolloid gum may be optionally added as a stabilizer to improve the yield of the cheese, and may be added in amounts of from about 0% to about 2%, and preferably from about 0% to about 0.8%. The hydrocolloid gum can be selected from the group comprising carrageenan, carob bean, guar and xanthan.
The invention provides a method for producing a soft, sliceable, unripened cheese-like product. Firming agents may optionally be added to firm the curd. Preferably, calcium chloride is added to produce a firm cheese curd and can be added in amounts of from about 0% to about 0.5%, preferably from about 0% to about 0.2%.
The invention also provides a method for producing a hard, sliceable, meltable, ripened cheese or cheese-like product. Firming agents may optionally be added to firm the curd. Preferably, calcium chloride is added to produce a firm cheese curd and can be added in amounts of from about 0% to about 0.5%, preferably from about 0% to about 0.2%.
Following step (a), above, a coagulating enzyme may be used to speed the coagulation process, and may be added in catalytic amounts. The coagulating enzyme may be selected from the group comprising rennet and its synthetic equivalents. Preferred rennet preparations can be selected from the group comprising AmericanPure, (SBI-Systems Bio-Industries, calf rennet purified via ion-exchange), Chy-Max (Pfizer, fermentationxe2x80x94using Escherichia coli K-12), Chymogen (Chris Hansen, fermentationxe2x80x94using Aspergillus niger var. awamori), ChymoStar (Rhxc3x4ne-Poulenc, fermentationxe2x80x94using Aspergillus niger var. awamori), Maxiren (Gist-Brocades, Fermentationxe2x80x94using Kluyveromyces marxianus var. lactis), Novoren (Marzyme GM) (Novo Nordisk, Fermentationxe2x80x94using Aspergillus oryzae). Kosikowski, F. V. and Mistry, V. V. (1997), xe2x80x9cCheese and Fermented Milk Foods,xe2x80x9d 3rdedn., F. V. Kosikowski, L. L. C., Westport, Conn., pp. 395 and 698.
Following step (a), above, a bacterial culture may optionally be added to the resulting mixture. The bacterial cultures can be added to the mixture to produce a desired flavor of cheese or to aid in acid development. Furthermore, these bacterial cultures may be added in lieu of, or in addition to, a coagulating agent. The types of bacterial cultures to be added to the mixture is obvious to one skilled in the art of making cheese. Examples of bacterial cultures that may be added to the mixture include, but are not limited to, Lactobacillus Bulgaris, Lactobacillus Lactus, Lactobacillus Helveticus, Streptococcus Thermophilus, Streptococcus Cremoris, Streptococcus Diacetilactis, Streptococcus Lactus, Streptococcus Durans, Leuconostoc Faecalis, Leuconostoc Citrovorum, Leuconostoc Dextranicum. The bacterial cultures may be added individually, or as mixtures of bacterial cultures that contain 2 or more different species of bacteria. Appropriate mixtures of bacterial cultures are readily apparent to one skilled in the art.
A mixture comprising curds and whey results after step (d), above. The whey may be separated from the remainder of the above and below described mixtures by at least one of the methods selected from the group comprising draining, straining and filtering. Preferably, said separating results in elimination of from about 50% to 80% of the whey, and even more preferably, results in elimination of from about 60 to 70% of the whey.
After separating a percentage of the whey from the rest of the above described mixtures, the mixture is further processed to produce the appropriate type of cheese or cheese analog. The processing required to produce various types o cheeses or cheese analogs at this stage in the method is obvious to one skilled in the art of cheese-making. The mixture is also salted to improve flavor and texture. The salting agent can be selected from the group comprising sodium chloride. The salted, processed mixture is poured into molds to shape the cheese. The mixture in the molds may also optionally be externally pressed to remove moisture from the cheese or cheese analog. The resulting cheese composition after comprises from about 2% to about 17% soy isolate.